An Assessment of the Status of Biodiversity in the ... - IUCN

Field sampling techniquesSampling methods were designed to identify and quantify all groups of vertebrates, someselected groups of invertebrate taxa, and floral communities in representative habitats withinthe study area. Flora was enumerated using the belt transect technique (25m x 5m). Distinctvegetation types were identified according to the vegetation structure and composition. At least3 replicates were taken from each vegetation type to accommodate the floristic variationswithin a site. Abundance of each plant species in a given plot was recorded according to Braun-Blanquet method (cited in Sutherland, 1996).The fauna sampled regularly included all groups of vertebrates and also two groups ofinvertebrates (butterflies and molluscs) for which there is adequate information in Sri Lanka.Standard sampling techniques specified in Sutherland (1996) were adopted, with slightmodifications to suit the existing field condition. Fish were sampled by cast netting (10 randomcasts/site/strata) and by observing the commercial catch. Herpetofauna in islands and mainlandwere sampled along transects (50m x 5m) and by placing pitfall traps. Birds were documentedby 0.5 hour point counts (100m radius; 3 sites/strata). Mammals were documented in aqualitative manner, using direct observations and indirect methods (defecation, tracks).Butterflies in islands and mainland were documented along 50m x 5m transects. Terrestrialmolluscs were documented in 2m x 5m belt transects. Aquatic crustaceans and molluscs weredocumented in a qualitative manner, using the commercial catch, and collection of specimens.Identification and nomenclature of fauna and floraThe fauna and flora of Maduganga were identified and classified using the guides stated inTable 2 below:Table 2Guides used for the identification and taxonomy of flora and faunaGroupSourceFlora Dassanayake, M. D. & Fosberg, F. R. (eds.) (1980 - 1991); Dassanayake, M.D., Fosberg, F. R. and Clayton, W. D. (eds.) (1994 - 1995) Dassanayake, M.D., and Clayton, W. D. (eds.) (1996 - 1999)Fish Pethiyagoda (1990); De Bruin et al. (1994)Amphibians Dutta & Manamendra-Aarachchi (1996)Reptiles Deraniyagala (1953); De Silva (1990)Birds Harrison & Worfolk (1999)Mammals Phillips (1980)Butterflies D’Abrera (1998)Molluscs Brackish water - Pinto (1986); Terrestrial - Naggs & Raheem (2000)Crustaceans Pinto (1986); De Bruin et al. (1994)6